Being an "Expert"

Virtually every psychological study that investigates expert "performers" - from chess grandmasters to concert pianists to brain surgeons - concludes that what separates these individuals from their peers is the amount of "deliberate practice" they are willing to endure. If there is an innate difference between Yo Yo Ma and a mediocre cellist, or between Tiger Woods and your golfing uncle, it is a willingness to practice, and not an innate aptitude for the cello or the 9 iron. As K. Anders Ericsson, a cognitive psychologist at Florida State University, wrote in his influential article "The Role of Deliberate Practice in the Acquisition of Expert Performance," "The differences between expert performers and normal adults are not immutable, that is, due to genetically prescribed talent. Instead, these differences reflect a life-long period of deliberate effort to improve performance." Ericsson estimates that it takes approximately 10,000 hours of "deliberate practice" before a person can become a world class expert. If Marc Yu puts in an average of 1500 hours of practice per year (probably a lowball estimate), and he began practicing the piano at the age of two, then it's possible that he's already crossed the 10,000 hours threshold.

http://scienceblogs.com/cortex/